those words, baby and mother healthy. An expert right here? Again ashton. Delivered more than a thousand babies. Yep. Take us inside the hospital right now. First several hours for a first mom. Well, first thing to recognize, george, is that whether this is occurring at st. Mary's or all over this country in labor and delivery units, the same basic things occur. In obstetrics we have two patients on our hands at least. When she's admitted first thing you do you get the maternal vital sign, blood pressure, bake blood tests and assess the well-being of the baby with an external heart rate monitor. If everything looks good and her onbstetricians have examined her we let nature take its course. We know kate had econocomplicat complicati complications. She had a healthy pregnancy for now everything looks good. Your guess, how long will it take? The crystal obstetric ball. When you talk about how long labor lasts we look at four FACTORS, THE FOUR Ps, FIRST ONE Is the power. How hard is the uterus contract contracting, the next one is the passenger. How big is the baby and what position is the baby in to navigate the pelvis, the third one the pelvis, the bony structure of the pelvis, the size and its configuration and the last one, mind/body connection, psyche, all of those factors so important. Out of time. Birthing pool? Well, it's very relaxing for a lot of women. If she wants to be underwater and her doctors give the green light, she can do that. Jen ashton, thanks very much.

This transcript has been automatically generated and may not be 100% accurate.

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